Perhaps - like me - you love playing cards. Maybe you even know a lot about them. But there are some fascinating things about playing cards that a lot of people don't know. Have you ever studied them closely, and considered some of the details and patterns that lie hidden on their faces, waiting to be discovered?

As a playing card connoisseur, you might already know some of the interesting facts that this article covers, in which case you can join me in celebrating and appreciating them. And for the rest of us, please join me in diving into the world of playing cards, and learning about some of the lesser known trivia and treats that playing cards can offer!

CARD CALENDAR

Playing cards have a long history dating back hundreds of years, and their exact origin remains a matter of speculation. But there certainly are some fascinating ways in which the make-up of a deck can be explained. It has often been observed how a deck of playing cards corresponds to a calendar in many remarkable respects:

● 2 colours: The two colours of red and black correspond to the two parts of each day, namely daytime and night.
● 4 suits: The four suits correspond to the four seasons of spring, summer, fall, and winter.
● 13 values: The thirteen cards in each suit correspond to the 13 weeks in each quarter, and to the 13 lunar cycles.
● 12 courts: The 12 court cards correspond to the 12 months in a year.
● 52 cards: The 52 cards in a deck correspond to the 52 weeks in a year.

Is this symbolism deliberate, or is it just a happy coincidence? Either way, this makes for a great story! There's also a wonderful viral video of magician Justin Flom performing a slick routine to commemorate Veterans Day, and in which he mentions and explains some of this symbolism as found in a deck of cards [link].

MATHEMATICAL MAGIC

Playing cards also have several mathematical secrets built into them, and here are some of the patterns and fun you can have when you combine numbers with a deck of cards:

Perfect Shuffles: Faro shuffles are a specialized type of shuffle where the cards are inter-weaved together exactly one card at a time. If you do eight perfect faro out-shuffles, the deck will return exactly to its original order! You can see someone accomplish this impressive feat in a video clip here. (If you're really keen, you can learn about the mathematics behind all this, in a 25 minute video explanation by Dr Victoria Noquez here.)

Possible Shuffles: The number of different ways to arrange a single deck of 52 cards is staggering - it's a number greater than the number of atoms on earth! Just how many exactly? 52! (52 factorial = 52x51x50x49 ... x2x1). That's an 8 with around 67 zeroes! Or to be exact: 80658175170943878571660636856403766975289505440883277824000000000000
This means that even if you shuffled a new arrangement every single second, it would still take millions of years to cover every combination. So next time you shuffle a deck of cards, think about how unique that arrangement and that moment really is. Each time you pick up a shuffled deck, it's almost certain that the exact order of the cards in your hands has never existed before, and will likely never exist again!

Infinite Eights: The negative space between all the pips on the Eight of Diamonds actually depicts the figure eight!

Addition Test: If you add up all the values of the cards in a deck (assigning 11 for the Jack, 12 for the Queen, and 13 for the King), plus add one for the Joker, you end up with 365 - exactly the same as the number of days in a year. Add a second Joker, and you have one for each day in a leap year. Is this perhaps further proof that there's a card calendar hidden in a deck of cards?!

Spelling Test: Take a regular deck (minus the Jokers), and spell the names of all the cards from Ace through King, dealing off one card every time. Remarkably, the very last card you will deal for the G of KING will be the final card in the deck! In essence this means that the total number of letters in the values of all the cards coincidentally happens to add up to exactly 52. Try it for yourself, and be amazed!

PRODUCTION TRIVIA

The production and printing of playing cards is also fascinating, and there are some interesting details that tell us something about when and how playing cards are made, if you know where to look.

USPCC: The United States Playing Card Company is the world's largest producer of playing cards today. It has more than 700 employees, and produces over 100 million decks each year. That is the equivalent of more than 5 billion individual playing cards - almost as many as the number of people on the planet right now!

Glue core: Did you know that playing cards contain glue, and do you know why? Most playing cards are made out of two layers of paper glued together, but the glue isn't merely there to stick these two layers together. It also plays an important role of ensuring that the cards are opaque - which means that you can't see through them when they're held up to the light. In addition, a coating is applied to cards near the end of the production process, but this is designed to help protect them from moisture. In other words, paper playing cards aren't just paper!

Bevelled edges: Playing cards are printed on large sheets, and when machines cut these sheets into individual cards, this creates a tiny bevel on the edge of the cards. Depending on the direction of the cut, decks are considered to have a traditional cut or a modern cut. This tiny difference usually goes unnoticed, except by people who weave the cards together one by one in what is called a faro shuffle.

Dated decks: It's possible to date a deck of cards made by the USPCC by the code printed on the Ace of Spades. The code used is a letter followed by a number, and the letter gives an indication of what year the deck was manufactured. (Want to learn more about this? Head to this article.)

Casino decks: Casinos have to be very careful that playing cards don't become marked, or that cheaters can pull an extra card out of their sleeves. According to one casino worker, playing cards are changed at least once each eight hour shift, and in many games they are replaced much more often than that, especially when they are handled a lot by players. So that you can't sneak them back into a game, casinos carefully mark used cards with ink, clip their corners, or drill a hole in the center. These are sometimes referred to as cancelled casino cards.

So there you have it, some fascinating facts about playing cards that the average person typically knows little about. Maybe knowing something about the finer points of playing cards will help you look at them differently the next time a deck hits your table! At the very least, it will give you some interesting ammunition to share with family and friends between hands in your next card game, and you can cement your credentials as a true playing card connoisseur!

Author's note: I first published this article at PlayingCardDecks.com here.

Thanks for sharing that! I use some of that information when performing in certain situations. I ask the audience if they knew that....and it always gets them interested. They have more of an appreciation for cards after learning some of the interesting facts.